1. Field of the Invention
The present invention relates to an improved chip disposer using permanent magnets applied to dispose of chips or iron chips produced from a machine tool such as a machining centre.
2. Description of Background Art
In recent years, disposal of a large amount of chips or iron chips produced by cutting work in a machine tool became a severe problem with the progress of unattended operation in a machine factory. Particularly, chips deposited on a workpiece, jig, pallet, table and the like on an NC (Numerical Controlled) machine tool such as a machining centre could cause the following problems:
(1) The deposited chips disturb unattended exchange of a workpiece in an exchange station of the workpiece. The chips also reduce working efficiency remarkably even in exchange operation of the workpiece by an operator.
(2) The chips are scattered in a carrying path for the workpiece and the pallet and a pallet pool, and the working environment is deteriorated.
(3) The chips deposited on the workpiece can damage tools.
In order to solve the above problems, a method is now utilized in which the chips are flowered together with cutting oil, but this method is not sufficient.
Further, an apparatus exists which utilizes magnetic force to attract the chips deposited on a workpiece, jig or table for removing the chips. FIG. 10 shows the apparatus. In FIG. 10, numeral 131 denotes a head stock and numeral 132 denotes a main shaft. A taper shank 133 of a chip removing apparatus 130 is detachably fitted in the main shaft 132. The apparatus 130 includes a magnetic core 134 and a coil 135 and forms an electromagnet when the coil 135 is excited by energizing devices 136 and 137. The electromagnet attracts chips deposited on a workpiece, jig or table and removes them from the machine tool.
Generally, a sufficiently large attractive force can not be obtained from the electromagnet when the number of turns of the coil 135 is not sufficiently large or when current flowing through the coil is not sufficiently large. However, when the number of turns of the coil 135 is increased, the apparatus can not be compact, while when large current flows through the coil, the energizing devices 136 and 137 are made larger and chips are attracted to the devices resulting in electric leakage.